Perforation gun with angled shaped charges

ABSTRACT

A perforation gun which provides a means to create perforations required for the hydraulic fracturing of rock formations for the production of natural gas, oil, and other oil well fluids and further comprises a gun body assembly having an inserted carrier tube to nest shaped charge canisters with built in primers, conical liner, and explosive material. The charges are positioned in various angular patterns along various phase angles to create specifically directed perforation tunnels which puncture scalloped areas of the aforementioned gun body and subsequently penetrate through the wellbore, well casing, well cement, and into the rock formations for the release and removal of natural gas, oil, and other oil well fluids after hydraulic fracturing.

RELATED APPLICATIONS

There are currently no applications co-pending with the presentapplication.

FIELD OF THE INVENTION

The presently disclosed subject matter is directed to hydraulicfracturing of rock formations for the production of natural gas, oil,and other well fluids. More particularly this invention relates to wellperforation guns that use shaped charges to create directed hydraulicfracturing perforation tunnels.

BACKGROUND OF THE INVENTION

One (1) of the largest and more important industries in the world isenergy production. A simple basic fact is that the world in general andAmerica in particular needs energy.

There are many different types of energy: coal, hydro, solar, nuclear,wind and fossil fuels (non-coal fossil fuels). Coal has a reputation forbeing dirty and shares with nuclear a reputation as being a source ofdangerous pollution. Hydro power has been almost fully developed in theUnited States. Wind and solar power while attractive are unproven asreliable large scale sources of power. However, fossil fuels are wellknown and widely used sources of power, particularly for vehicle andheating fuels.

Fossil fuels have been widely used for well over a hundred years. Themain problems with fossil fuels include price, which is a function ofavailability. Recovering fossil fuels is become increasingly moredifficult as new fields are seldom encountered. However, newer recoverymethods have increased the amount of fossil fuels that can be obtainedfrom known fields.

The newer recovery methods include hydraulic fracturing. Hydraulicfracturing is based on creating and propagating fractures in ageological formation by first using explosive shaped charges to createperforation tunnels and subsequently pumping liquids and propantmaterial through the perforation tunnels into the geological formation.Hydraulic fractures enable gas and petroleum contained in the sourcerocks to migrate into a well where the fossil fuel can be recoveredusing well-known techniques.

Hydraulic fracturing is not without its problems and technicalchallenges. Creating effective perforation tunnels is not in itselftrivial. Producing controlled explosions within a well bore to createeffective perforation tunnels is even more difficult. First theexplosion must be at the proper well depth. This typically requiresdrilling a well to the proper depth followed by the insertion of one (1)or more perforation guns containing explosive charges. Then, for maximumeffect the perforation tunnels must be directed towards a desireddirection. Since that location might be up, sideways, down, or at aparticular angle the explosive charges should be both shaped to form atight, effective perforation tunnel and directed towards the properorientation. At well depth both of these desired attributes aredifficult to accomplish.

Therefore, a new perforation gun that produces tight, controlled, andeffective perforation tunnels in the desired direction would bebeneficial. Even more beneficial would be a new perforation gun capableof producing controlled and enhanced perforation tunnels.

SUMMARY OF THE INVENTION

The principles of the present invention provide for a new explosiveperforation gun that produces tight, controlled, and effectiveperforation tunnels in the desired direction. The perforation gun iscapable of producing controlled and enhanced effect perforation tunnels.

A perforation gun that is in accord with the present invention includesan outer gun body assembly having a straight steel pipe casing withinternal female threads at each end, a plurality of external recessedareas, and an orientation slot extending inward from one (1) end of thesteel pipe. The perforation gun further includes a carrier tube assemblyhaving a linear charge tube, a first collar having an external alignmentpin that is dimensioned to slide into the orientation slot and which islocated at one (1) end of the charge tube, a second collar at theopposite end of the charge tube, a plurality of shaped charge saddleslots through the charge tube, and a plurality of shaped charge bodyapertures through the charge tube, wherein the plurality of shapedcharge saddle slots and the plurality of shaped charge body aperturesform a plurality of shape charge holders, and wherein the charge tube isa length of straight steel pipe that is slightly shorter than said outergun body assembly. The perforation gun further includes a plurality ofshaped charges, each having a shaped charge saddle, each having a chargebase, and each of which is located in an associated shape charge holderof the plurality of shape charge holders. The carrier tube assembly isinserted into the outer gun body assembly such that the alignment pinslides into the orientation slot to control the orientation of theplurality of shape charges with respect to the external recessed areas.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and features of the present invention will become betterunderstood with reference to the following more detailed description andclaims taken in conjunction with the accompanying drawings in which likeelements are identified with like symbols and in which:

FIG. 1 is an exploded perspective view of a perforation gun 10 havingangled shaped charges according to a preferred embodiment of the presentinvention;

FIG. 2a is a side cut-away view of the perforation gun 10 shown in FIG.1;

FIG. 2b is a section view of the perforation gun 10 taken along sectionline I-I of FIG. 2a;

FIG. 3 is a perspective view of a carrier tube assembly 30 of theperforation gun 10 shown in FIG. 1;

FIG. 4 is a side cut-away view of the perforation gun 10 shown in FIGS.1 and 3 in use;

FIG. 5 is an exemplary perforation tunnel vector diagram for theperforation gun 10 shown in FIGS. 1, 3, and 4 according to a preferredfan-shot embodiment 80;

FIG. 6a is an exemplary perforation tunnel vector diagram for theperforation gun 10 using a down-shot embodiment 83;

FIG. 6b is an exemplary perforation tunnel vector diagram of alimited-entry embodiment 85 of the invention; and,

FIG. 6c is an exemplary fracture perforation tunnel vector diagram of acombined-limited-entry-fan-shot embodiment 90 of the invention.

DESCRIPTIVE KEY

10 perforation gun

20 outer gun body assembly

21 steel pipe casing

22 female threaded region

23 male threaded coupling

24 orientation slot

25 recessed area

26 male threaded region

30 carrier tube assembly

32 charge tube

33a first collar

33b second collar

34 set screw

35 orientation/alignment pin

37 carrier interior space

40 perforation tunnel vector angle

42 shaped charge saddle slot

43 shaped charge body aperture

44 clip feature

60 perforation tunnel vector

80 fan-shot embodiment

82a first fan perforation tunnel vector

82b second fan perforation tunnel vector

82c third fan perforation tunnel vector

82d fourth fan perforation tunnel vector

82e fifth fan perforation tunnel vector

83 down-shot embodiment

84 down-shot perforation tunnel vector

85 limited-entry embodiment

86a first limited-entry perforation tunnel vector

86b second limited-entry perforation tunnel vector

86c third limited-entry perforation tunnel vector

86d fourth limited-entry perforation tunnel vector

86e fifth limited-entry perforation tunnel vector

90 combined limited-entry-fan-shot embodiment

92a first combined perforation tunnel vector

92b second combined perforation tunnel vector

92c third combined perforation tunnel vector

92d fourth combined perforation tunnel vector

92e fifth combined perforation tunnel vector

120 shaped charge canister

125 shaped charge saddle

130 charge base

200 well casing

300 geological formation

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The best mode for carrying out the invention is presented in terms ofits preferred embodiment, herein depicted within FIGS. 1 through 6c, anda person skilled in the art will appreciate that many other embodimentsof the invention are possible without deviating from the basic conceptof the invention, and that any such work around will also fall underscope of this invention. It is envisioned that other styles andconfigurations of the present invention can be easily incorporated intothe teachings of the present invention, and only one particularconfiguration shall be shown and described for purposes of clarity anddisclosure and not by way of limitation of scope.

The terms “a” and “an” herein do not denote a limitation of quantity,but rather denote the presence of at least one of the referenced items.

Referring to FIGS. 1, 2a, and 2b, the principles of the presentinvention provide for a perforation gun 10 that uses angled shapedcharges 120 to explosively perforate geological formations 300. Theperforation gun 10 is first placed inside a well casing 200 (see FIG.4), the shaped charges 120 are directed to the desired direction, andthen the shaped charges 120 are exploded to create fracture patternsthat assist extraction of natural gas, oil, and other oil well fluids.

The perforation gun 10 comprises an outer gun body assembly 20 thatreceives and accurately positions a carrier tube assembly 30. The outergun body assembly 20 and the carrier tube assembly 30 are aligned andmachined so as to position a plurality of internal shaped charges 120which create interactive angled perforation tunnel vectors intogeological formation 300 (see FIGS. 4 through 6c) upon detonation. Thosevectors aid hydraulic fracturing of the geological formation 300 and therelease and capture of natural gas, oil, and other oil well fluids.

Each outer gun body assembly 20 includes a variable length of aspecially machined straight steel pipe casing 21 that has internalfemale threaded regions 22 machined at each end, and a plurality ofexternal machined recessed areas 25. The female threaded regions 22enable any number of outer gun body assemblies 20 to be attachedtogether in an “end-to-end” manner using interconnecting male threadedcouplings 23 (see FIG. 4). The recessed areas 25 of the outer gun bodyassembly 20, which are preferably circular, oval, or rectangular shapedto a depth of approximately one-half (½) of the thickness of the steelpipe casing 21 are arranged to align with corresponding shaped charges120 that are positioned within the carrier tube assembly 30. Upondetonation, the recessed areas 25 provide weak sections of steel pipecasing 21 that are readily punctured by the perforation jets produced bythe exploding shaped charges 120.

The outer gun body assembly 20 includes an orientation slot 24 along aninside surface at one (1) end of the steel pipe casing 21. Theorientation slot 24 accurately orientates the carrier tube assembly 30within the outer gun body assembly 20. The orientation slot 24 works inconjunction with a corresponding orientation/alignment pin 35 of thecarrier tube assembly 30. The orientation/alignment pin 35 is acylindrically-shaped feature having a diameter sized to provide asliding fit in the orientation slot 24.

During loading of the carrier tube assembly 30 into the outer gun bodyassembly 20 the orientation/alignment pin 35 is positioned at a trailingend of the carrier tube assembly 30 during insertion. To completelyinsert the carrier tube assembly 30 into the outer gun body assembly 20the orientation/alignment pin 35 slides into the orientation slot 24 toproperly establish the correct theta (rotational) position of thecarrier tube assembly 30 within the outer gun body assembly 20. Completeinsertion happens when the orientation/alignment pin 35 abuts the inwardend of the orientation slot 24. This longitudinally and rotationallypositions the carrier tube assembly 30 within the outer gun bodyassembly 20 which is then held in place with a recessed snap ring.

Referring now primarily to FIGS. 2a and 3, the carrier tube assembly 30includes a linear charge tube 32, a first collar 33a, a second collar33b, a plurality of shaped charge saddle slots 42, and a plurality ofshaped charge body apertures 43. The charge tube 32 is a length ofspecially prepared straight steel pipe slightly shorter than the outergun body assembly 20 into which it is installed. The charge tube 32enables attachments to the collars 33a, 33b via respective threaded setscrews 34 (only one shown in FIG. 2a). The first collar 33a includes theaforementioned integral orientation/alignment pin 35 which protrudesperpendicularly to engage the corresponding orientation slot portion 24as previously described.

The shaped charge saddle slots 42 comprise circular, rectangular, oroval-shaped features that are machined through the charge tube 32 toallow insertion of a shaped charge saddle 125 of a shaped charge 120placed inside the carrier tube assembly 30. Each shaped charge saddleslot 42 has a corresponding shaped charge body aperture 43 that ismachined through an opposing surface of the charge tube 32. Each shapedcharge body aperture 43 comprises a circular or cylindrical-shapedmachined feature having a diameter dimensioned to receive a charge base130 of a shaped charge 120.

Referring now primarily to FIG. 2b, the system 10 uses a plurality ofcommercially-available shaped charges 120 such as those available fromOWEN OIL TOOLS™, TITAN SPECIALTIES, LTD™, and others. Each shaped charge120 has a cylindrical shaped charge base 130 having a single protrudingconical-shaped end that forms the shaped charge saddle 125. Each shapedcharge 120 also has a contained explosive, a conical metal liner, ashaped charge body, and built in primers. The direction of a shapecharge 120 can be variably directed via the joint angular and positionalcharacteristics of a shaped charge saddle slot 42 and a shaped chargebody aperture 43 that directs an explosion toward a recessed area 25.Selective pairings of shaped charge saddle slots 42 and shaped chargebody apertures 43 can angle a shaped charge 120 toward an generally inthe direction of one end of the carrier tube assembly 30 along a planewhich is parallel to and horizontally extending extends along the centerof the carrier tube assembly 30 (see FIGS. 5 through 6c).

Referring now primarily to FIG. 2a, located along the perimeter of eachshaped charge body aperture 43 is at least one (1) machined clip feature44 which comprises a malleable, finger-shaped appendage that can be bentand positioned using a hand tool against the charge base portion 130 ofa shaped charge canister 120 to secure the shaped charge canister 120 inposition.

Referring again to FIG. 3, the carrier tube assembly 30 can beincrementally positioned such that the shaped charge saddle slots 42 andshaped charge body apertures 43 align the shaped charge canisters 120 atselective phase angles along a spiral or straight pattern from one (1)end of the carrier tube assembly 30 to the other. It is understood thatvarious phase angles such as one-hundred-eighty (180°) degrees, ninety(90°) degrees, sixty (60°) degrees, and the like may be used based upona user's preference to produce a desired geological perforationformation 300 and hydraulic fracturing effect.

Referring now to FIG. 4, which is a side cut-away view of the system 10in use, the system 10 includes the outer gun body assembly 20 withthreaded couplings 22 at each end. Male couplings 23 provide malethreaded regions 26 that mate with female threaded region 22. Thisenables any number of desired outer gun body assemblies 20, eachcontaining a carrier tube assembly 30 to be coupled together to create aselective length system 10.

Upon detonation, the angular positioning of the shaped charges 120 withrespect to corresponding shaped charge saddle slots 42 and shaped chargeapertures 43 produce directed perforation tunnel vectors 60 thatpenetrate the well casing structure 200, any surrounding well casingcement, and the surrounding geological formation 300. The outer gun bodyassemblies 20 and the carrier tube assemblies 30 may be specificallymachined with the aforementioned features 42, 43 to enable positioningof the shaped charges 120 at various phase angles and angularorientations to create desired geological formation perforations andsubsequent fracturing.

Possible perforation tunnel vectors 60 are illustrated in FIGS. 5through 6c. FIG. 5 shows a preferred fan-shot pattern 80. The carriertube assembly 30 is configured with shaped charge 120 oriented andarranged at a selected phase angle to form a fan-shot pattern 80 upondetonation. The fan shot pattern 80 is produced by arranging groups ofshaped charges 120 at phase angles that progressively increase along thelength of the carrier tube assembly 30. The shaped charges 120 producemonotonically decreasing (measured in an X-Y plane with 0° toward theright) perforation tunnel vectors 60 comprising first fan perforationtunnel vectors 82a (such as 135°) near the left hand side of the carriertube assembly 30, smaller angled second fan perforation tunnel vectors82b (such as 120°) further way from the left hand side, substantiallyperpendicular third fan perforation tunnel vectors 82c at the middle ofthe carrier tube assembly 30, smaller angled fourth fan perforationtunnel vectors 82d (such as 60°) past the middle of the carrier tubeassembly 30, and still smaller angled fifth fan perforation tunnelvectors 82e (such as 45°) near the right hand side of the carrier tubeassembly 30. The actual number and angle of the shaped charge canisters120 and resulting fan perforation tunnel vectors 82a, 82b, 82c, 82d,82e, may be selectively varied to produce a desired fracturing effect.

FIG. 6a shows another set of preferred perforation tunnel vectors 60arranged to produce a down-shot pattern 83. The down-shot pattern 83 isproduced by arranging groups of shaped charges 120 at fixed angles, suchas 135° along the length of the carrier tube assembly 30. The down-shotpattern 83 is directed downward. However, by inverting the carrier tubeassembly 30 an up-shot pattern that is directed upward can be produced.The actual angle of the shaped charge 120 and resulting down-shotpattern 83 (or up-shot pattern) can be varied to produce a desiredgeological formation 300 perforation tunnels and subsequent hydraulicfracturing effect.

FIG. 6b shows another set of preferred perforation tunnel vectors 60arranged in a limited-entry pattern 85. The limited-entry pattern 85 isproduced by arranging groups of shaped charges 120 to produceperforation tunnel vectors 60 having angles that monotonically vary fromthe nearest end of the carrier tube assembly 30 toward 90° at the middleof the carrier tube assembly 30. For example, first limited-entryperforation tunnel vectors 86a near the left hand side of the carriertube assembly 30 at an angle of 45°, second limited-entry perforationtunnel vectors 86b further toward the middle of the carrier tubeassembly 30 at an angle of 60°, third limited-entry perforation tunnelvectors 86c at the middle of the carrier tube assembly 30 that areperpendicular to the carrier tube assembly 30, fourth limited-entryperforation tunnel vectors 86d located to the right of the middle of thecarrier tube assembly 30 having an angle of 120°, and fifthlimited-entry perforation tunnel vectors 86e nearest the right hand sideof the carrier tube assembly 30 at an angle of 135°.

The limited-entry pattern 85 shown in FIG. 6b produces limited-entryperforation tunnels 86a, 86b, 86c, 86d, 86e that collectivelyconcentrate the explosive forces from the shaped charges 120 to producea desired geological formation 300 perforation tunnel and subsequenthydraulic fracturing effect. Again, it should be noted that the anglescan be selectively varied to produce a desired perforation tunnelgeometry and subsequently hydraulic fracturing effect.

FIG. 6c shows another set of preferred perforation tunnel vectors 60,but this time arranged in a limited-entry-fan-shot embodiment 90. Thelimited-entry-fan-shot embodiment 90 is produced by arranging groups ofshaped charges 120 to produce perforation tunnel vectors 60 havingangles that spread out in a wide angle across the carrier tube assembly30 from each end to the middle, with the middle perforation tunnelvectors 60 being perpendicular to the carrier tube assembly 30. Theshaped charges 120 are arranged along selected phase angles to producethe combined limited-entry-fan-shot embodiment 90.

The combined limited-entry-fan-shot embodiment 90 is envisioned asproducing a plurality of first combined perforation tunnel vectors 90a(say at 135°) near the left hand side, second combined perforationtunnel vectors 90b (say at 45°) left of the center of the carrier tubeassembly 30, third combined perforation tunnel vectors 90c at the centerof the carrier tube assembly 30 and at 90°, fourth combined perforationtunnel vectors 90d right of the center of the carrier tube assembly 30(say at 135°), and fifth combined perforation tunnel vectors 90e nearthe right hand side of the carrier tube assembly 30 (say at 45°). Suchan arrangement of combined limited-entry perforation tunnel vectors 90a,90b, 90c, 90d, 90e diffuse the perforation jets from the system 10 atsome locations while concentrating them at the middle of the carriertube assembly 30 so as to produce a desired geological formation 300perforation geometry and subsequently hydraulic fracturing effect. Thecombined limited-entry-fan-shot perforation tunnel vectors 90a, 90b,90c, 90d, 90e are described as emanating at suggested angles; however,the actual number and angles of the shaped charges 120 and resultingperforation tunnel vectors 90a, 90b, 90c, 90d, 90e may be selectivelyvaried to produce a desired fracturing effect.

It is envisioned that other styles and configurations of the presentinvention can be easily incorporated into the teachings of the presentinvention; only one (1) particular configuration is shown and describedfor purposes of clarity and disclosure and not by way of limitation ofscope.

The preferred embodiment of the present invention can be utilized bytechnicians skilled in the art after having received appropriateinstructions in the configuring and assembly of the system 10. Afterinitial purchase or acquisition of the system 10, it would be installedas indicated in FIGS. 1 through 4.

The method of using the system 10 may be achieved by performing thefollowing steps: procuring a number of matched outer gun body assemblies20 and carrier tube assemblies 30 having desired overall lengths, phaseangles, and being machined with properly aligned recessed areas 25,shaped charge saddle slots 42, and shaped charge body apertures 43 so asto produce a desired geological formation perforation effect withsubsequent hydraulic fracturing upon detonation; inserting an initialcarrier tube assembly 30 into a matching outer gun body assembly 20until obtaining full engagement of the orientation/alignment pin 35within the corresponding orientation slot 24 and securing in place witha snap ring; inserting the system 10 within a horizontal well casingstructure in a conventional manner; detonating the system 10 remotely ina normal manner to produce perforation tunnel vectors 60 being projectedinto surrounding geological formation(s) at desired angles anddirections, thereby producing a desired geological formation 300perforation effect with subsequent fracturing effect using the presentinvention 10.

The method of utilizing additional units of the system 10 may beachieved by performing the following steps: inserting any additionalcarrier tube assemblies 30, as desired, into respective outer gun bodyassemblies 20; arranging the outer gun body assemblies 20 in a desiredsequential order in a linear manner; joining adjacent outer gun bodyassemblies 20 by threading the male threaded regions 26 of theconnecting couplings 23 to the female threaded regions 22 of theadjacent outer gun body assemblies 20; and, performing detonation,perforation, and subsequent hydraulic fracturing as described above.

It is further understood that during preparation and assembly of thesystem 10, as described above, any number or sequence of patterns fromthe system 10 can be produced; including the fan shot pattern 80, thedown-shot pattern 83, the limited-entry pattern 85, and the alternatecombined limited-entry-fan-shot pattern 90. The various patterns canalso be mixed to produce a desired geological formation 300 perforationjet geometry and subsequent hydraulic fracturing effect.

The foregoing descriptions of specific embodiments of the presentinvention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention and method of use to the precise forms disclosed. Obviouslymany modifications and variations are possible in light of the aboveteaching. The embodiment was chosen and described in order to bestexplain the principles of the invention and its practical application,and to thereby enable others skilled in the art to best utilize theinvention and various embodiments with various modifications as aresuited to the particular use contemplated. It is understood that variousomissions or substitutions of equivalents are contemplated ascircumstance may suggest or render expedient, but is intended to coverthe application or implementation without departing from the spirit orscope of the claims of the present invention.

What is claimed is:
 1. A perforation gun, comprising: an outer gun bodyassembly having a first straight steel pipe with internal female threadsat each end, a plurality of external recessed areas, and an orientationslot extending inward from one end of said first straight steel pipe; acarrier tube assembly having a linear charge tube which has an externalsurface, a first collar having an external alignment pin dimensioned toslide into said orientation slot, said first collar fits over one end ofsaid charge tube into an installed position radially outward of saidexternal surface, a second collar that fits over the opposite end ofsaid charge tube, a plurality of shaped charge saddle slots through saidcharge tube, and a plurality of corresponding shaped charge bodyapertures through said charge tube, wherein said each of said pluralityof shaped charge saddle slots and corresponding ones of said pluralityof shaped charge body apertures form a plurality of shaped chargeholders, and wherein said charge tube is a length of a second straightsteel pipe slightly shorter than said outer gun body assembly; and aplurality of shaped charges, each: having a shaped charge saddle, eachhaving a charge base, and each of which is located received andrestrained in an associated shaped charge holder one of said pluralityof shaped charge holders by its respective shaped charge saddle insertedin a corresponding shaped charge saddle slot and being angularlyadjustable therein; wherein said carrier tube assembly is inserted intosaid outer gun body assembly such that said alignment pin slides intosaid orientation slot so as to control the orientation of said pluralityof shaped charges with respect to said external recessed areas; andwherein said first collar is locked into position relative to saidcharge tube by insertion of said alignment pin in said orientation slot.2. The perforation gun according to claim 1, wherein said internalfemale threads are further comprise a machined surface.
 3. Theperforation gun according to claim 1, wherein said external recessedareas are machined approximately half way through said first straightsteel pipe.
 4. The perforation gun according to claim 1, furtherincluding a male coupling having threaded male members on each end,wherein said male coupling is attached to one end of said first straightsteel pipe by threading into said internal female threads, and whereinsaid male coupling enables attachment of a second perforation gun. 5.The perforation gun according to claim 4, comprising two individualperforation guns joined together by male coupling.
 6. The perforationgun according to claim 1, wherein said first collar is locked to saidcharge tube by a set screw.
 7. The perforation gun according to claim 6,wherein said position of said first collar can be adjusted on saidcharge tube such that said alignment pin engages said orientation slotto controllably orientate the position of said shaped charges withrespect to said recessed areas.
 8. The perforation gun according toclaim 1, wherein each shaped charge saddle slot is machined through saidcharge tube to allow insertion of a shaped charge saddle.
 9. Theperforation gun according to claim 8, wherein each shaped charge bodyaperture is machined through said charge tube to allow insertion of acharge base.
 10. The perforation gun according to claim 9, wherein eachshaped charge is secured in position by a malleable appendage thatextends from said carrier tube to contact that shaped charge's chargebase.
 11. The perforation gun according to claim 1, wherein saidplurality of shaped charges are orientated with respect to said recessedareas by said orientation slot so as to produce a desired geologicalfracturing effect.
 12. The perforation gun according to claim 11,wherein said plurality of shaped charges are orientated with respect tosaid recessed area to produce a fan shot pattern.
 13. The perforationgun according to claim 12, wherein said fan shot pattern is produced byarranging groups of shaped charges at phase angles that progressivelyincrease along said carrier tube assembly so as to produce monotonicallydecreasing perforation tunnel vectors.
 14. The perforation gun accordingto claim 11, wherein said plurality of shaped charges are orientatedwith respect to said recessed area to produce a down-shot pattern. 15.The perforation gun according to claim 14, wherein said down-shotpattern is produced by arranging groups of shaped charges at fixedangles along said carrier tube assembly.
 16. The perforation gunaccording to claim 11, wherein said plurality of shaped charges areorientated with respect to said recessed area to produce a limited-entrypattern.
 17. The perforation gun according to claim 16, wherein saidlimited-entry pattern is produced by arranging groups of shaped chargesto produce perforation tunnel vectors having angles that monotonicallyvary from each end of said carrier tube assembly toward 90° at themiddle of said carrier tube assembly.
 18. The perforation gun accordingto claim 11, wherein said plurality of shaped charges are orientatedwith respect to said recessed area to produce a limited-entry-fan-shotpattern.
 19. The perforation gun according to claim 18, wherein saidlimited-entry-fan-shot pattern is produced by arranging groups of shapedcharges to produce perforation tunnel vectors having angles that spreadout in a wide angle across said carrier tube assembly from each end tothe middle of said carrier tube, with the middle perforation tunnelvector perpendicular to said carrier tube assembly.
 20. The perforationgun according to claim 1, wherein said plurality of shaped charge saddleslots further comprise circular, rectangular or oval shaped featuresthrough said charge tube to allow insertion of a shaped charge saddle.21. The perforation gun according to claim 1, wherein a shaped charge issecured in position within at least one of said plurality of shapedcharge holders by a clip.
 22. The perforation gun according to claim 21,wherein said clip is selectively engaged with said shaped charge topermit insertion and retention of said shaped charge in said at leastone of said plurality of shaped charge holders.
 23. The perforation gunaccording to claim 1, wherein at least a portion of said plurality ofshaped charge holders are orientated to receive a shaped charge at anon-perpendicular angle with respect to said external surface of saidcharge tube.
 24. A perforation gun according to claim 23, wherein saidat least a portion of said plurality of shaped charge holders areorientated to receive said shaped charge at varying angles with respectto said external surface of said charge tube.
 25. A perforation gunaccording to claim 24, wherein said charge tube has a midpoint along itsaxial length and said varying angles of said shaped charge holdersdecrease along said axial length of said carrier assembly from saidmidpoint to each end, creating a limited entry explosive pattern.
 26. Aperforation gun according to claim 25, wherein said at least a portionof said plurality of shaped charge holders are additionally orientatedin a spiral pattern along the axial length of said charge tube.
 27. Aperforation gun according to claim 25, wherein said shaped charge issecured in position within at least one of said plurality of shapedcharge holders by a clip.
 28. The perforation gun according to claim 27,wherein said clip is selectively engaged with said shaped charge topermit insertion and retention of said shaped charge in said at leastone of said plurality of shaped charge holders.
 29. A perforation gunfor creating a pattern of perforation tunnels in at least one of a wellcasing and a rock formation, said perforation gun comprising: an outergun body having an interior space, an exterior surface and alongitudinal axis, said exterior surface having a plurality of recessedareas forming a spiral pattern along said longitudinal axis; and acarrier selectively axially mounted in a preselected position withinsaid interior space of said outer gun body, said carrier having: alongitudinal axis coincident with said longitudinal axis of said outergun body; an axis perpendicular to and extending outwardly from saidlongitudinal axis at a preselected point along said longitudinal axisdividing said longitudinal axis into two portions; a plurality of shapedcharge bodies; and a plurality of spaced apart shaped charge holders,extending along said longitudinal axis, sized and shaped to: (i) receiveand restrain each of said plurality of shaped charge bodies interiorlyadjacent to corresponding ones of said plurality of recessed areas ofsaid outer gun body and form a coincident preselected spiral patternalong with longitudinal axis; and (ii) expel a focused explosive chargetherefrom along a charge vector extending radially outwardly from saidlongitudinal axis and forming an included phase angle with saidperpendicular axis; at least a plural portion of said plurality of saidshaped charge holders being mounted in a preselected pattern along saidlongitudinal axis such that said charge vectors are non-intersecting andindependently form monotonically decreasing included phase angles withrespect to perpendicular axis creating a limited entry explosivepattern.
 30. A perforation gun according to claim 29, wherein saidcarrier has two ends and said perpendicular axis is located at amidpoint along said longitudinal axis.
 31. A perforation gun accordingto claim 29, wherein said carrier has two ends and a midpoint along saidlongitudinal axis and a portion of said varying phase angles of saidshaped charge holders monotonically increase along said longitudinalaxis from said midpoint to each end, creating a fan-shaped explosivepattern and a portion of said varying angles of said shaped chargeholders monotonically decrease along said longitudinal axis from saidmidpoint to each end, creating a limited entry explosive pattern.
 32. Aperforation gun according to claim 29, wherein the shape of saidplurality of charge holders further comprise at least one of saddleapertures and body apertures which are selected from the groupconsisting of circles, ovals and rectangles.
 33. A perforation gunaccording to claim 29, wherein said carrier further comprises at leastone collar defining a spaced apart relationship between said carrier andsaid outer gun body.
 34. A perforation gun according to claim 29,wherein at least one of said carrier and said outer gun body furthercomprise an alignment pin mountable in a corresponding orientation slotin at least one other of said carrier and said outer gun body toregister said carrier with said outer gun body such that said pluralityof charge holders are aligned with said plurality of said recessed areasof said outer gun body.
 35. A perforation gun according to claim 29,further comprising at least one coupler mounted on an end of said outergun body to affix at least one other perforation gun in a linear, axialrelationship with said perforation gun.
 36. A perforation gun accordingto claim 29, wherein at least one of said plurality of shaped chargebodies is secured in position within at least one of said plurality ofshaped charge holders by a clip.
 37. A perforation gun according toclaim 36, wherein said clip is selectively engaged with at least one ofsaid plurality of shaped charge bodies to permit insertion and retentionof said shaped charge body in one of said plurality of shaped chargeholders.
 38. A perforation gun according to claim 37, wherein said clipis malleable.
 39. A perforation gun according to claim 20, wherein saidshaped charge saddle slot features form a perimeter which directlyreceives and restrains said shaped charge saddle.
 40. A perforation gunaccording to claim 39, wherein said shaped charge saddle slot featuresare integral with said carrier tube.